The present invention relates to improvements in dental syringes of the type disclosed in my prior U.S. Pat. Nos. 3,436,828; 3,581,399; 3,900,954; 4,198,756; Des. 226,767 and co-pending patent application Ser. No. 314,768, filed Oct. 26, 1981, which are particularly adapted for precisely positioning various composites and/or other viscous dental material in a dental restorative procedure. Heretofore, such dental materials have been packaged in jars and other containers which a dentist would purchase in bulk, and which then required the dentist to parcel out of the bulk supply in small amounts the material necessary for a particular procedure. As a result, a dentist had to rely on his judgement to ascertain how much material was needed for a particular procedure. This trial and error method of determining the amount of material necessary, more frequently than not, proved to be wasteful practice because invariably more material than was necessary would be mixed or used. As such materials may be relatively costly, any amount so wasted only increased a dentist's operating costs.
Also, the taking of such material from a bulk supply to the placement of the material to a patient's tooth is a tedious and time-consuming operation and oftentimes resulting in voids occurring in the filling of a tooth cavity, by the spatuling of such material into a cavity. The syringe constructions as disclosed in the foregoing noted patents were conceived to enhance the application of such current dental materials in a dental procedure and required the dentist to first parcel out the amount of material required and load the syringe with such amount.
The objects of the present invention are intended to further advance the art of restorative dentistry and the packaging and dispensing of various dental materials such as the viscous composite resins, impression materials, light activated materials and the like. The light activated materials, in particular, pose the additional problem that such material, when exposed to light will tend to set or cure in a relatively short period of time. Therefore, the dispensing of such light activated material from a bulk supply presented a further handling problem, viz. the exposure of such material to curing light in effecting the transfer of the material from its bulk supply to the patient's mouth.